He’s a brat, and he’s been a brat for years and years and years.
He should do the right thing with the kid and his family, which means a proper apology in person, a new phone and probably a small financial gesture in addition or the hospitality tickets etc.
Separately to that he should face serious sanctions by the Premier League.
Players have had suspensions for giving fans the finger, and as mentioned earlier there was cantona at the other end of the spectrum. He should get a van somewhere in the middle of those, and probably because it was a kid it should skew more towards severe than lenient.
I’d say a 4 match ban. More than you’d get for a red card in a match. A proper punishment.