Hi. As per your history and clinical photo, looks like ?scabies. Its parasitic infestation. It spreads from one person to the other. So its necessary that all the family members to be treated at one go. Apply permethrin 5% cream from neck to toe at night and take bath the next day. Apply the entire tube at one go. Repeat the same after a week. This procedure to be done by all family members. Put 2 to 3 days clothes, bedsheets and bedspreads for wash. Take tab levocetrizine 5mg at night for 3 weeks. In spite of treating you'll have itching for 3 to 4 weeks.
Next Steps
Best is to consult Dermatologist for confirmation of the diagnosis
Health Tips
avoiding sharing soaps, towels and clothes.