Does she understand that Meadow is "working" and not horseplaying? Maybe explaining the difference might be helpful. Maybe sugguesting that she will part of the training process, she would be helping in keeping you safe in the near future. Does she understand that Meadow will now be a permanent member of the family and will be expected to go where you do. That Meadow will be you safe in her home and in public in general. I think if you make her part of the training process - she might be more understanding. Offer to do a demo as part of the gathering so that all members actually see & understand the difference from working or pet dog. I don't know... just some random thoughts.
Tricia