One Big Happy Family?

The recounting of the tribes and their various descendants generally follows a pretty steady pattern. The first name contains no prefix and the rest are prefixed with a למ"ד as follows: פלוני... לפלוני... לפלוני... וכו. An anomaly is found, however, in the children of גלעד. We find איעזר, לחלק, ואשריאל, ושכם, ושמידע, וחפר. The latter four are prefixed with a וי"ו. Why?

In a discussion within the דקדוק WhatsApp group, it was suggested that the explanation for this might lie in the turn of events at the end of the next week's פרשה in which the daughters of צלפחד are instructed that they must marry within the שבט in order that their father's portion of the land not end up belonging to another שבט. Perhaps these are the individuals, or the families of the individuals, who married those daughters. Since their families were ultimately intertwined, instead of the traditional למ"ד separating each name, a וי"ו החיבור is used to indicate that in the end, they were all one big family.

However, I recently discovered another anomaly for which I have no answer:

כ"ו:כ"ג

בְּנֵי יִשָּׂשכָר לְמִשְׁפְּחֹתָם תּוֹלָע מִשְׁפַּחַת הַתּוֹלָעִי לְפֻוָה מִשְׁפַּחַת הַפּוּנִי