Re: General Question
<resisting smart aleck remarks referring to wet shoes>
really, need to know size/design to best advise you.
You can put some water in the boat while its on the trailer and look for leaks out, especially around rivets, through-hull fittings, etc. However water pressure isn't as great this way.
Launch the boat and observe for a while; check the same areas. Lay down newspaper or paper towels to see where it first gets wet.
Do you have a closed-in bilge? If so you should have a bilge pump and a float switch. When it activates you know you have water, if from no other source, a leak.
Larger boats have water alarms, too. My bilge pump switch lights when it's on, including when the flaot switch activates.
Carry a bailer and a hand pump at least. a set of bungs (plugs) can also be a lifesaver.
If your boat starts leaking, head to shore, call for help; some boats you'd pull the drain plug while running to drain it.
Fixing a leak at sea and on shore are usually two different things. Can't advise on fixing one until we know more about the boat in general and the leak in particular.
If you are not sure if you have a float switch, bilge pump, bilge or drain plugs, don't use your boat, and for cod's sake don't take your child out, until you learn more about it and what to do in emergencies. Take an experienced boater out with you first (after you take the USCG safety course--in fact, take it with your wife and children).