Even if your child is potty trained, at time, they may be unwilling or unable to tell you when their bladder is full. Unfortunately, those times will usually happen when you're away from the comforts of your own toilet. You already know that being a mom requires you to have some amazing super powers, so now you can add mind reader to the list after multitasker and crisis negotiator. And as your first mission, you're going need to know how you know your kid needs to pee without them telling you.
Recognizing the signs that your kid has to potty can help you avoid messy clean-ups and painful urinary tract infections. If they aren't letting you know when they have to go, you should begin to recognize things like crossing legs and fidgeting as tell-tale signs that your little one is holding on to the urge to pee.
In addition to watching for signs, it can help to encourage your toddler to use the potty throughout the day, as The Bump suggested. The gentle nudge can get him in the habit of going on his own. You can also set a good example by letting your child know when you feel the urge to go. It may seem a little weird at first, but when you find yourself cleaning up fewer accidents, you'll be glad you did.