It is NOT your dad. Your dad is the fifth gym leader. To get to the gym leader in the 4th, you must try all those piles of ashes and try to fall into the leader's room.And P.S. the 4th gym leader is Flanairry, the fire type leader.
go to the 5 gym
In order to get The gym leader to appear in her gym, go to the Pokemon contest arena in the north end of the city. There, you will meet your mother and get a tux, as well as have a chat with the gym leader. She will then meet you at the gym.
You go off and train it and start defeating the gym leaders
You have to go to the Lighthouse in Sunyshore City and he will be there. Talk to him and he will go back to the gym. When you get to the gym, Flint will still be standing there. Talk to him and he will move.
You go to Fortree City to take on on the flying type gym leader!
go to the next citi
go to fortree city and battle winona
Go to Viridian city and beat Giovanni,the gym leader
go back to the city were the gym leader wasn't there
Go beat the 6th gym leader ^^, that is in Fortree City.
go to the galatic warehouse after defeating the 4th gym leader
Go to Fortree City. Fight Gym Leader Winona. Win. Then get the HM Fly. ^^
After defeating the rivals at the weather institute, go towards fortree and then u'll have a battle with may after which she'll give it to u Actually, u can only use it after defeat GYM leader in Fortree City. She uses Flying Pokemon. So, you should have Electric and Rock Pokemon.
go to the seafoam islands after defeating the other fourteen gym leaders
After defeating the 5th gym leader (Norman) in Flora Sky, the next goal is to get to the 6th gym leader. Go to maulville city and go to the right of the city.
Go to vermillion, use digglet cave to get to the next