All Blood Symbiotes are host to the same pathogenising fungus. The reproduction of the fungus does not create a unique new organism but a replication of the same. Blood Symbiote hosts can hear whispers from the symbiote. They can see shared visions from other hosts and they all are drawn together. There are Blood Symbiotes who worship and look for the Mother. There are different accounts of who and what the Mother is. Some believe she is the first Blood Symbiote while others say that the original fungus lives independent of any human and mutant host. They see expansive fields of living red matter calling to them. Others even say that the Mother has infected the earth itself and burrowed deep into its core. No matter what the Mother is most of those who hear the whispers agree that the Mother is real.
Many Blood Symbiotes go off in search of the Mother but those who come back have never been able to find her. The Cult of the Mother is dedicated to finding the Mother and serving her will.