[en.wikipedia.org]
My Notes: My understanding is that Isis was married to Osiris. He died. She moved in with the brother of Osiris named Horus. Then she gave birth to the 4 sons of Horus. I believe 1 of these sons may be called Horus, son of Osiris. I have proposed a connection of this Osiris son with Amset... since he has the human face, whereas the other sons of Horus are depicted with Animal faces.

Other sources:
Plutarch - Osiris and Isis:
[penelope.uchicago.edu]

[www.egyptianmyths.net]
The works of the classical writers identified her with Persephone, Tethys, Athene, etc, just as Osiris was associated with Hades, Dionysos and other foreign gods.

[www.egyptianmyths.net]
"Whenever Isis left Horus in the evening while they were in hiding in the papyrus swamps near Buto, she was accompanied by seven scorpians. Three of the scorpians preceded her, Petet, Tjetet, and Matet and made sure that the path ahead was safe. At her side were the scorpians, Mesetet and Mesetetef. Bringing up the rear were Tefen and Befen."

[www.touregypt.net]
"The region where all these things took place was situated in Delt, and the Island in the Papyrus Swamps, where Isis brought forth the child and hid him, was near the famous double city of Pe-Tep, which was commonly called Buto by the Greeks."