Which part of speech is 'together' in the sentence?

[learning54]

Hi teachers,
Which part of speech is 'together' in the following sentence? It is an adverb, isn't it? Could one one of these synonyms 'simultaneously', 'at the same time', or 'in union' be synonyms for the sentence given? They don't sound very well to me, could you suggest one please?
Septuplets are seven children who are born together.

Thanks in advance

 

[Rover_KE]

All your suggestions are wrong, I'm afraid.

You need '. . . at the same birth', as they always emerge one after another.

('...simultaneously' makes my eyes water just thinking about it.):shock:

Rover

 

[learning54]

Hi Rover,
Thank you for both of your replies.

Best,
L54