When?

At what age do you think it's ok to ask family members to babysit for the day? I want to take my 4 year old to the amusement park tomorrow but I have a 6 week old and my husband has to work. I'm not sure I want to try to take both of them by myself. I was thinking of asking my parents to watch the baby for the day. Is this ok or would you wait until he's older. I'm sure my parents would say yes, its just I feel bad asking. I don't want him to be a burden on them.