Baby oil is a rather thin oil that very easily drips on clothing. This product contains mineral oil and a fragrance--because it is an oil, it may not come out of clothes through a regular wash.You can treat the stain before washing with readily available, inexpensive products.
Lay the clothes on a solid surface, such as a table. Spread cornflour over they oil stains. Cornflour will absorb some of the oil--let it sit on the stains for 5 to 15 minutes.
Brush off the cornflour, using a dry sponge. Pour liquid dish detergent directly on the baby oil stain and rub it into the fabric with a damp sponge. Allow this to sit for several minutes (about 15 minutes).
Rinse the stained areas beneath warm running water. Keep rinsing until the dish soap has been removed--with it, much of the oil should be removed as well.
Re-apply dish detergent to the areas. Alternatively, you can apply a pre-wash stain treatment (stick or spray).
Place the clothes in your washing machine. Add washing powder as well and run the clothes through a warm (or hot, if the material allows it) water wash.
Dry the clothes on a clothes line, indoors or out. Inspect the clothes for stains after they have dried. If any remain, reapply dish detergent (brush it in with a damp sponge) and wash the clothes again in warm water with washing powder.