Massaging baby with which oil is good for healthy skin?

None if normal skin: Unless baby has skin conditions such as eczema, excessive dryness, heat rash/fungal infections etc...Normal healthy skin of baby is best left alone. Avoid excessive bathing/cleansing of baby's skin. If your baby has concerning skin condition, please consult doc first before treating it. Good luck.

Baby skin: Since babies can absorb through their skin, any oils which are not nut oils are best. Avoid, massage oils based on almond oil for example. Aquaphor ointment is a common oil based moisturizer that can be used.

Baby oil fine...: Regular baby oil without perfumes and scents is fine, but it's not necessary for healthy baby skin. What's more important is sunblock and sun protection - especially for those toddlers and babies who are going outside. There are some great "baby" sunblocks which I use on my kids pretty regularly... We usually skip the baby oil.