my baby girl is 18 months old.she had 3 episodes of fall from the bed in her sleep at night in the last 5 months with bumping on her head . each time she develops a bluish bruise and subsequently a dent forms in her forehead. no other symptoms present.i am worried if these falls could have resulted in serious brain damage or any cognitive impairment in my baby. also i want to know if these dent in her head that appears on frowning will go away with time or is permanent