Just popping in here real quick. At this time, we don’t have a way to share a different campaign from inside the source campaign, in this case, the first campaign in your drip series from your last campaign. You would have to encourage them to find the initial email and share it.
If you would like to see this feature added, I would encourage you to submit the idea here: https://ideas.activecampaign.com/ideas/new. All submissions are reviewed by our Product team who are welcome to new ideas.
While we don’t currently have a way to forward a different email than the one the contact is currently in, there could be a potential way to automate it so that it is easier. You could build a short wait after the last campaign and then a Send an Email action that resends the first campaign. This would cause the contact not to have to go back and search for the initial email if they wanted to forward it to friends.
You would just want to let the contacts know to expect it in your last campaign so they don’t think they accidentally started the drip over.
Let me know if you need any clarification or have any other questions.