Double yolk 1 strong live chick 1 attached embreo help?

[TJR]

We just hatched 10 eggs, the 9th however I had to intervene once I cleared the dried membrain from chicks eyes it finished the work itself an hatched n my hand under a heat lamp. However it rolled over in my hand an I discovered it was a doubke yolk. The second yolk had a undeveloped fetus. its been well over 24 hours an the live chick is strong an healthy but the fetus/yolk sack is dried but still attatched 2 my chick I dont know what 2 do any advise would b great

Getting worried thank you

 

[Melissa Rose]

This thread has a lot and may be of help.
https://www.backyardchickens.com/forum/viewtopic.php?id=104245

I hatch tortoises and sometimes there are twins. You have to separate them. If one is already dead then I would tie the umbilicus as closely to the live chick as possible with a small piece of thread then sever it past the thread! Good luck