Summarize:

Set up a routine for feeding your guinea pig. Try to feed them at the same times in the day. Also, try to feed them in a place they feel safe, such as their cage or play area. A consistent schedule will mean that your guinea pig begins to associate you with food; this is key to forming a bond with your guinea pig. Remember that whoever feeds the guinea pig will likely be the person they bond with first. If multiple people are going to oversee feeding, give them an assigned time. You can feed them in the morning, and your daughter in the evening. Or feed the guinea pig together so it gets used to both of you. The goal of using snacks is to have the guinea pig associate you with food. This is a positive association that will help the guinea pig to feel comfortable around you. At first, just place the treats in the cage. Then after a few days, hold it in your hand and see if the guinea pig will come closer to you. If they won't come all the way, toss the food gently in their direction. Have the guinea come closer each time you offer snacks. Eventually, it will begin to take it out of your hand and will begin to feel less nervous around you. Make sure you are talking in a calm yet happy voice as you feed them. Grass, vegetables, and some fruit are all tasty treats for your guinea pig. Try foods such as cucumber, carrots, banana slices, romaine lettuce, and seedless apples. Pet stores also sell treats marketed for guinea pigs and other small animals. Make sure you read the labels first; some have a lot of high fructose corn syrup and are full of empty calories. Give all treats in moderation. Too much sugar, empty calories, or just overfeeding can cause your guinea pig to become obese. This can have serious health complications for your pet and may shorten its lifespan.
Be consistent about your guinea pig's feeding schedule. Use hand feeding to develop a sense of trust. Treat your guinea pigs to healthy snacks.