Aiden (now 4.5) started piano when he was 3.5 years after he begged for 6 months to either learn violin (his first choice) or piano.
I found a teacher that said we could try it. We kept it short (20 minutes per lesson, eventually extending to 30 minute when he wanted to carry on/was focused. If we got there and he was clearly not in the mood the teacher would show him the guitar, recorder or a drum kit, always ending with a tie back to the piano. Otherdays she would just discuss music with him - tempo, beats, composers etc. Some days they would play with shakers and tambourines and triangles etc and march around together just having fun.
We always stopped when he said he was tired and I never ever pressured him to practice either - I would suggest it and if he was keen we would.
After 6 months he wanted to take a break and I agreed since the lessons were getting a bit expensive to not do it seriously kwim?
6 month break and then he has now started Suzuki violin and has expressed an interest to return to piano. We are getting an old piano from my brother and I will teach him the basics here until he shows he will practice nicely.
the big thing is to let him enjoy it more than anything.
