I kicked a football over neighbours fence and they took it inside their houseWatch this thread
1) Knock on the door, apologize for your football accidentally going over their fence and then politely ask for the ball back.
2) Buy a new football and don't mention anything about the incident.
Tell her you'll ring the bizzies as she's stolen it and she will get a criminal record; and Police Interceptors will turn up with a film crew.
Or apologise and ask very nicely for it back. So you don't have a neighbour hating you.
Moved to Advice on everyday issues
We get that many balls over our fence I've started to collect them. When renovating our garden, I used my new chainsaw to slice through them all and chuck them back.
Be careful next time. Buy a new one and suck it up.