To do so, you have to click on the Ask Friends button. Then a pop up will appear and you have to select from your friends list the ones you think will response to your request. Be sure to pick the active ones so that you have a higher chance of getting Soaps.
When your friend accepts your request, they’ll get one as well. The bad news is that the Soaps are not giftable. If you have extra Soaps, you can’t gift them to your friends.
If you have extra Horseshoes, you can also unlock this requirement by paying 15 Horseshoes. The amount is the same whether you have 0 or 9 Soaps.
Have you already completed the Time for the Annual Pre-School Bath goal? Did you have a hard time collecting Soaps for this mission?