Miriam's Influence

I was asked the following question the other day: In three separate places in Chumash, Chur is mentioned and Rashi takes pains, each time, to inform us that he was the son of Miriam.

First: Shemot 17:10, when Chur and Aharon support Moshe in his defense of the Jews during their war with Amalek.

Second: Shemot 24:14, when Moshe appoints Aharon and Chur to be the counselors of the Jews while he is away on Har Sinai.

Third: Shemot 35:30, when Chur's grandson Betzalel is appointed to lead the creation of the Mishkan.

Why does Rashi go out of his way to mention Chur's mother each time?

My first thought was that there were midrashim on each pasuk identifying Chur's lineage, and Rashi was only citing those midrashim, but I could not find any such midrash, on any of the pesukim.

So I have an idea which I would not deem "peshat", but which I like in any case: Each of these cases involves Chur in a different role, and in each case he channels the influence of his mother, Miriam.

In defending the Jews against Amalek, Chur channels his mother Miriam's defense of the Jews as a midwife (Shemot 1:17), and her defense of Moshe as he floated in the river (Shemot 2:4-9).

In counseling the Jews, Chur channels his mother Miriam's counsel to Amram and Yocheved to have more children (Sotah 12a), and her counsel regarding Moshe and Tziporah's relationship (Bamidbar 12:1, Rashi there).

In creating the Mishkan, Chur's grandson channels Miriam's act of connecting the Jews to Gd in the dance after they crossed through the Sea (Shemot 15:20-21).

And Rashi highlights this by commenting, each time, "Chur is the son of Miriam."

Just a thought.