It is narrated from Hazrat Aisha (may Allah be pleased with her) that the Prophet (peace and blessings be upon him) said: For a boy, two equal goats should be sacrificed for aqeeqah, and for a girl, one goat.
Hadith Referenceمسند احمد / مسند النساء / 24028
Hadith Gradingحکم دارالسلام:حديث صحيح وهذا إسناد حسن من أجل عبدالله بن عثمان