Frisky Business (EP)

All four must be done in the same playthrough. You will earn Double Your Melonz, Double Your Fun and Giddy Up while going for all four.

The first time will happen in Chapter 9 after you take the test.
The second will be in Chapter 10 when Gertrude and Jenny come home with you from Melonz.
The third and fourth times are both at the beginning of Chapter 11.

If you are following the Roadmap, this trophy is part of Run #3. The walkthrough for this can be found here.