belts?

my mom has a 05 sienna with 12k miles on it, and whenever its kinda of chilly outside or even somtimes hot and the engine is cold you start it and when it turns over and starts it makes a squeeking sound for bout 1 second like the belts are slipping, is this normal?

When it's cold out, there is often dew, frost, or condensation that gets on the belts and pulleys. Once dry, the slipping stops. When a belt slips it wears it out at an accellerated rate. Check the belts for tightness, you can get a tension measurer from Napa for less than $10. The belts should last a lot longer than 12k mi. It is normal for them to stretch and have to be adjusted, especially just after replacement.