You should take your child to the doctor. You would not want to be in a situation where complications arise later.
My sister had to 'pass' hers and my parents had to watch for it. Good luck.
That happened to someone I know- their daughter swallowed a penny. This is gross, but what they did was check her feces for it until it passed through. Unfortunately, I was babysitting when it did :P
Whew!! I was a bit nervous. My kid did the same thing, at the same age, I of course called the doctor and spoke w/ the advice nurse. I was told to monitor for any breathing changes or difficulites and make sure there were no other abnormal upper respiratory changes or tummy aches. I was then told that 98.9% that all would be well just to be on stool watch for the next 72 hours. Sure enough like clock work the coin came out in the wash, so to speak. Doing fine and well and continues to be an active 3yr old. All will be well with yours too.
God bless :)