Is it permissible for a person to marry the sister of his foster-sister—who is the daughter of her mother's co-wife from the same husband—after he was suckled by her mother?

If a person is suckled by a woman with a forbidden suckling (five sucklings within two years), then this woman's paternal sister becomes forbidden to him, because she becomes his maternal aunt through suckling. This is based on the Prophet's (peace and blessings be upon him) saying: "What is forbidden by lineage is also forbidden by suckling."