Hate to break it to you, aggressive behaviour is a normal, healthy part of toddler (and human) development. Between language an communication skills letting them down when they need to communicate their fierce need for independence most and the ability to know what they want, but not know how they can get it - frustration and anger are sure to follow. Undeveloped impulse control means your little angel is going to act on those impulses, leaving friends, sibling or anyone within shooting range on the receiving side of some bites, scratches and bruises.
Please remember - this is, albeit undesirable, completely normal. Your child is not set up to be the next Bundy, he won't be enrolling in anger management when he's an adult and his wife will not have to wear those truly conspicuous sunglasses indoors.
Normal - Yes. Acceptable - Absolutely not. We are here to guide our sprouts and show them what society thinks is cute, what is cool, and what is a complete and utter NO.
Let your toddler know that aggressive behaviour is NOT OKAY by, in a calm manner, diffusing the situation first and then motivating your little one to express the feelings that led to the outburst in words - making these emotions tangible by giving them names often makes the tot feel more in control. On top of the feelings thing, try to reward good behaviour and give attention to actions that are desireable by offering praise wherever and whenever you can. Rather than giving your toddler such intense and undivided attention when he's misbehaving, try switching it up and giving the same attention to good acts - your undivided attention is the ultimate reward for your toddler.
Praise verbal expressions of emotions and wants. When he announce he's feeling angry, tell him "well done for recognizing that emotion so well, what is making you angry?" or when he politely asks for a turn to play with a toy, even if the request is not fulfilled, praise his approach to trying to get the item "well done for asking for a turn, I know you didn't get what you wanted, does that make you feel frustrated?" If the toddler admits to having a negative feeling, guide him through it by saying things like "let's see if there might be a different toy for you to play with" or " let's wait a while, maybe the toy will be available soon"
Tips for dealing with aggressive behaviour
1. Your actions have consequences
If your child is in a setting where he misbehaves and gets aggressive with friends, diffuse the situation by removing him from it. Sit him down and explain that he can't participate in the game if he cannot behave himself, and then prompt him to tell you when he's ready to behave himself and return to playing.
*Note: this is not a two way conversation, do not reason with your toddler or offer hypotheticals like "how would you feel if..." At this age they don't have the cognitive maturity to put themselves in another's shoes. They do, however, understand consequences.
2. Calm down before trying to calm your child down
Now I know, it's tough, after "diffusing" a situation for the fifth time at a play date you feel like blowing shouting, hitting and telling your child who's the boss here. Sorry to say - this won't help one bit, it will only intensify an already electric situation. Cool your jets, then work on cooling your toddler's.
3. Be Clear and concise
If it's "no", it should be acted on immediately and clearly. Don't give your toddler the chance to hit his brother for the third time before you intervene - this is confusing him as to where the boundaries really are.
4. Consistency is key
Try to react to every episode the same way you did before. A predictable response will create a pattern for your toddler and help him categorize "right" and "wrong"
5. Offer alternatives
When everyone has hunkered down and gotten themselves together, it's time for a frank conversation about what happened, why it happened, what the names of the emotions are that made it happen and what could have happened instead. Allow your child to lead the conversation and avoid sitting him down and preaching to him for hours on end without him learning anything himself (they tend to mute you when they see a certain expression and hear a certain tone).
6. Repeat the rule a million times
Ask your toddler to recite the rule back to you, this reinforces the behaviour you expect and sets it clearly in the foreground of what behaviour is a jay and what is a nay.
7. Limit screen time
I am yet to meet a mother, with toddlers, who can honestly say she doesn't use the TV as a makeshift babysitter for a couple of minutes while she gets lunch ready, while she cleans, while she gets dressed, while she packs school bags (the list can go on but you get the idea). It is, however, paramount that you monitor what your kids are watching. Cartoons often portray characters fighting, shouting, pushing and hitting - this can be fuel on a fire for a kid who is already struggling with frustration and aggression issues.
Our family's favourites are: Kiri and Lou, Heidi, Super Simple Songs (youtube), cocomelon, rainbow ruby and peppa pig.
8. Let them kids run
Some physical activity will help burn off some excess energy (otherwise used for tantrums and fighting). Provide plenty of opportunities for unstructured play - this will give them a chance to experience the independence they so crave. Chase them outside and let them get dirty, tired and (hopefully) well - behaved.
9. Encourage downtime
As well as being active it's also important to encourage your toddler to have down time, playing quietly by himself. Doing so means he learns to stimulate his imagination and to amuse himself without relying on you. While any time can be good, transitions from lunch to nap time, or supper to bedtime are ideal.
10. Don't be afraid to seek help
Sometimes you do need some help from a specialist to examine the what makes your little one tick and what straight up makes him boil over. People are complex. You are complex and so am I, a little mini-me who is struggling to understand the world is even more so.
Don't stress girl, this too shall pass