Has anyone started?? I have a 2.5 year old son who is fully trained now and my twins are starting to get really interested in the potty. Will sit on it after every meal (like their brother), will pull their pants down and will try to take their diapers off as well. My one twin pooped on the potty the other day when she showed us she wanted to sit down. I know they are only almost 17 months (Jan 1). Should I encourage it or wait as I read it’s best around 20 months. Thoughts?