|What happens if I open a 529 account for my child and then I die--who would control the account?|
That depends on the rules of your 529 plan. Some states, for example, permit the account owner to name a contingent account owner (also called a successor owner). This contingent account owner would then have all your ownership rights when you die. In other cases, ownership may pass to the designated beneficiary or to the guardian of the beneficiary (if the beneficiary is a minor child). And some states may treat the account as part of your probate estate--the account would then pass according to your will (or by the state's intestacy laws if you have no will).
Check your 529 plan's account ownership rules. You might also want to check with an attorney familiar with Section 529 and estate planning.