Well, you can convert from child to adult and then have bigger breasts. Other than that, you could find some cheat that might allow this. Without a cheat, I don't believe this can be done.
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What an odd question. There is no cheat code for bigger breasts for The Sims 2. In fact, you can't alter this attribute at all even when you create a new Sim.
There is NO cheat on Sims 3 for bigger breasts. Once you buy the expansion pack "Sims 3 Latenight" you can adjust your sims breast size.
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HMS Amore (a big boat)
No, you cannot have Sims 2 pets on Sims 3. You must have Sims 3 pets for Sims 3 or Sims 2 pets for Sims 2.