3 months is waaaay too short to expect anything.
Usually your clowns need to pair up first (1 male to 1 female).
You also need a very stable tank so that they don't feel stress and will want to do that spawning thing that they do.
Most people that have spawning clowns have established tanks that are 1 to 2 years old.
Then again, if you don't have time, you can always squeeze the eggs out of the female and squeeze the sperm out of the male and whoola, instant spawning
-Sorry, just kidding, it's 4:00 a.m. where I'm at.
