Verses with the word suckling in the Old Testament (3 verses):
The sword without, and terror within, shall destroy both the young man and the virgin, the suckling also with the man of gray hairs.
1 Samuel 15:3
Now go and smite Amalek, and utterly destroy all that they have, and spare them not; but slay both man and woman, infant and suckling, ox and sheep, camel and ass.
Therefore now thus saith the LORD, the God of hosts, the God of Israel; Wherefore commit ye this great evil against your souls, to cut off from you man and woman, child and suckling, out of Judah, to leave you none to remain;