My amazing wonderful usually always happy 2 and a half year old still hits and occasionally bites his new brother four months after his birth. He also kisses and cuddles and obviously adores him but I feel like he's getting more angry rather than less. I take him out just me and him for at least an hour at the weekend and pay him lots of attention although I'm shattered and we've just moved house so it can be hard. Love him so much feel so bad and want to limit the damage any tips gratefully received. Of course I should add I always pick up the baby and cuddle him move h away from toddler of he's being aggressive.
Toddlers are always jealous of babies, one way or another, and it's usual for it to express itself as physical violence as it's one of the few ways they have to express themselves. It was the only thing we ever used a timeout for, but I think tbh they just grow out of it as the baby gets older and less needy so there's less competition.
It's all normal. You need to give more general low level attention to your toddler in the day. Talk to baby about toddler, get toddler out of the house and play with him eg at the park. I find that ds will always be jealous of his sister no matter what I do but is better if I spend time with him every day eg reading a story at bedtime, giving him cuddles, asking him what's he's playing with etc etc.