My daughters behavior is very confusing to me, I am looking for advice how 'normal' this is. A bit of background, lovely baby, talked very early, walked late (17 months). Very funny and chill toddler and a great sleeper, rarely had tantrums or terribles 2s etc. Then I had a second baby when she just turned 3, her behaviour completely changed. She started having meltdowns a lot, I was so surprised how she was acting and I was very stressed. I got some help with my health visitor and her behavior finally settled (still had her moments). Then she started school in August and her behaviour is now worse. She screams a lot at home and has started hitting when she is extremely frustrated (multiple times a week), her triggers are things which dont seem 'normal' to me, i.e. me opening a packet for her when she can do it on her own, her thinking she rubbed off a bit of her facepaint, sometimes her tantrums just make no sense at all, they are much worse when she is tired. She behaves very well at school and goes to dance group, swimming, singing group and gets on great, if she is doing things, i.e. at an activity etc she is fine. In the house is where the behaviour is bad, now it has started at my parents. She has always loved going to my parents for sleepovers etc but her behaviour can be bad at theres too now. At school I have spoken to her teacher, described her as shy but very kind with a lot of friends. My MIL had her for a sleepover a few weeks ago and had to call us to return due to a meltdown because she told her she had to finish her craft. I looked into PDA but I dont feel this fits her? She wil happily get ready for school, shower, etc when asked, her tantrums are completely random to me and honestly I am walking on eggshells with her. Everyone who meets her says how lovely/sweet she is. I am just confused to be honest - does this sound regular behaviour? I am at the point I feel nervous for her to go to my parents etc which she has always done incase something sets her off. I will say she is great with her baby brother now, very caring and kind to him, however they can also fight badly.