You can make your baby pee in the same diaper twice. However, make sure that the diaper is completely dry after the baby has peed. Baby's skin that is exposed to moisture can cause diaper rash.
Most people buy diapers, washcloths, or baby blankets to keep in their pockets when removing their baby. Having different basic supplies in your pocket and knowing about improvisation can make diapers very easy for parents on the go.
There are other baby products which are very important for babies such as baby changing pad, pink baby blanket, baby muslin swaddle etc.
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