1. My favorite tip is first: to keep your baby from slipping around in the tub when you bath them, place a hand towel on the bottom of the tub and lay them on it once the tub is filled with an inch or two of water. Or if they can sit, fold up a bigger towel, so if they fall back it's there to cushion them. (Of course, it's still slippery so stay close by!) Just wring the towel out afterwards and keep completely open to dry fully by the next bath time.
2. For baby shampoo, soap, and lotion... Do you remember all those samples you got in the hospital, the first few weeks, or in parenting magazines? I saved them all! I use them for quick weekend trips and it saves space in our bags! If you are going for a longer period of time, you could buy a small bottle there or take your own. And remember to take advantage of the shampoo/body soap combinations that are offered... one less bottle to buy!
3. For diapers and wipes, buy them at your destination whenever possible. Even if they are slightly more expensive, it's worth not being loaded down! If you have a few extra and no space at the end of your trip, leave them at the next diaper changing station you see... some desperate parent will love you!
4. You could obviously buy baby food there, but since I make my own, I just take a mini-blender or food processor. I buy fresh fruits and veggies there (either cook to soft or buy "softer" ones), add water, and puree. You only need a few empty jars and a few spoons.
5. For flights, I recommend getting babies their own seat for longer trips (3 hours or more). It's worth the money to have free arms and you can bring two extra pieces of luggage (think pack 'n play and backpack). I had planned to breastfeed to keep our daughter's ears clear during take off and landing, but they wouldn't let me, since she had to be in the car seat. So I brought an empty bottle with a little sugar in the bottom. Once on the plane, I had the flight attendant fill it with water and I mixed it up a bit. Tastes good so they keep drinking and no worrying about not being able to bring liquid on flights.
6. I hate bare floors in hotels... who knows how dirty they are? So I brought a few of my daughter's alphabet blocks (seen below) in a bag with some of her toys. She had a clean place to play and also soft since some hotel floors could be really hard, even with carpet.
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