Potty Training!?

So I have tried for months it seems to set Charlie on the toilet without clothes on to only have him cry! He loved it with clothes on but once they were off he CRIED! David does it once with him and he thinks its the COOOLEST thing in the world! Yup not sure when it happened but Dads SO MUCH cooler then MOM! lol Well back to potty topic! So now he thinks its cool to sit on the toilet but I can't figure out how to get it through to him that its OK to go bathroom in the toilet! He will sit there forever just to get off get his diaper on and go! Sophs is just stubborn she can go and knows she should and she will hold it and pee in the hall once she gets out of the bathroom whether she has a diaper on or not. She is my stubborn one and Charles scared of getting in trouble! LOL such different Kiddos! So MOMS with potty trained kids any helpful tips would be very much appreciated!