We have a 7 year old chocolate and a 4 year old black Labrador. Both bitches, both spayed, both from working stock. Maisie the chocolate has always been driven and probably would have done well in the field, her brother is a field champion. She has always been 'an individual' and a tad territorial particularly if we sit at a table and any other dog dares to come to close. Intermittently 'hates' greyhounds, most terriers and the occasional red setter - will nip at them aggressively if she's on a lead. All irritating but manageable behaviours and all dependent on the day and her mood! Well exercised, 4 times a day minimum, loves swimming, retrieving etc. We walk 10 to 20 miles at least 4 times a week. However potential big problem emerging - son and husband got a baby last October. After she had met him for the first time Maisie began attacking her sister (Pippa) at night when she went into her crate. Maisie hasn't been in a crate for years, except when Pippa gets up in the morning. (Pippa still chews when the fancy takes her!) So we just got Maisie her own crate again - all fine... The first thing she did that was worrying was jump at the baby when our oldest was playing with him throwing him up into the air - fortunately he is 6'4" and even she cant jump that high. Let it go as we thought it was just excitement and that she possibly thought he was going to throw the baby for her to retrieve....??? Today, she launched herself down our front door steps at our neighbours toddler grandchild and was snapping at the little girl - mortified, upset doesn't even cover it! No damage at all but VERY frightening for all concerned - same thing she does with her sister and other dogs. Really fast movements circling and backing off but air nipping at the same time. HELP!
What an awful situation for you. I would recommend urgently seeking the help of a behaviourist before the unthinkable happens. Keep us posted x