My son has an asthma when he was like 1-2 years old . Right now thanks God its already gone. My question is, is it really true that asthma will come back when your older ?

Yes it will come back. It is due to it's cause that triggers asthma. So stay away from its triggers. Build a strong immune system. I believe that a person should try some activities like sports to create strong body but of course with supervision. Don't push too hard. Good luck on your child's health. God bless.