"But, you see, when a man’s got brains himself, there’s no knowing where they’ll run to; an’ a pleasant sort o’ soft woman may go on breeding you stupid lads and ‘cute wneches, till it’s like as if the world was turned topsy-turvy. It’s an uncommon puzzlin’ thing." (1.3.31)
Mr. Tulliver’s thoughts on the genetic lottery aside, these ramblings thoughts actually make an interesting statement on the unpredictable nature of families and children.
He had not a rapid imagination, but the thought of Maggie was very near to him, and he was not long in seeing his relation to his own sister side by side with Tom’s relation to Maggie. Would the little wench ever be poorly off, and Tom rather hard upon her? (1.8.26)
Mr. Tulliver’s sympathetic nature and his strong family loyalty are highlighted here. This realization is significant too, and it becomes the cornerstone of the advice he gives Tom regarding Maggie. Tom takes the advice, but he doesn’t uphold the compassionate spirit of it in regards to Maggie.
"Why do you come, then" she burst out, "talking and interfering with us and scolding us, if you don’t mean to do anything to help my poor mother - your own sister - if you’ve no feeling for her when she’s in trouble, and won’t part with anything though you would never miss it, to save her from pain." (3.3.57)
Maggie scolds her aunts and uncles here for their lack of substantial help after the family goes bankrupt. For Maggie, family should offer compassionate support and understanding, rather than judgment.
A deficit of more than five hundred pounds with the accumulating interest seemed a deep pit to fill [...]. On this one point there was entire community of feeling in the four widely differing beings who sat round the dying fire of sticks which made a cheap warmth for them on the verge of bed time. (4.2.4)
This scene paints a powerful picture of the Tulliver family after they go bankrupt. They are bound together by a shared misery and despite their wildly "differing" personalities, they come together around a pitiful fire each night, symbolically uniting as a family during a time of hardship.
She rebelled against her lot, she fainted under its loneliness, and fits even of anger and hatred towards her father and mother who were so unlike what she would have them to be - towards Tom, who checked her, and met her thought or feeling always by some thwarting difference - would flow out over her affections and conscience like a lava stream and frighten her [...] (4.3.35)
This is a pivotal passage for Maggie’s character. Though family love and loyalty are hugely important to her, it isn’t always easy to remain loving and loyal. Maggie struggles with her family and with the fact that you can’t choose your family. Her growing anger is vividly felt with the "lava" simile, too.
"I get weary of my home. And that cuts me to the heart afterwards that I should ever have felt weary of my father and mother. I think what you call being benumbed was better - better for me - for then my selfish desires were benumbed." (5.4.25)
This provides an interesting contrast to Maggie’s "lava" like frustration with her family. After growing angry with them, Maggie experiences inevitable guilt and wonders if feeling nothing at all (no more lava flows, so to speak) might not be better.
Maggie always writhed under this judgment of Tom’s: she rebelled and was humiliated in the same moment. (6.4.38)
This pretty much sums up Maggie’s tormented relationship with her brother. He has the power to humiliate her and make her feel ashamed. But Maggie also internally resists Tom’s judgment and hates him somewhat for it.
"I should not give you up on any ground but your own wish, Maggie," said Philip, colouring. "There are points on which I should always resist my father, as I used to tell you. That is one." (6.7.16)
Philip’s views on family provide an interesting contrast to Maggie’s views. Philip is willing to rebel and go against his father’s wishes if need be. Philip’s loyalties and love lie outside of his family, with Maggie.
"It’s respect and duty to her aunts and the rest of her kin as are so good to her, should have kept my niece from fixing about going away again, without consulting us." (6.12.12)
Aunt Glegg’s view of family duty is one of obligation – family members are practically beholden to one another and should never act independently. Or least not without consulting the family (i.e., Mrs. Glegg) first.
"If you were not to stand by your 'kin' as long as there was a shred of honour attributable to them, pray what were you to stand by?" (7.3.1)
Aunt Glegg may be judgmental and interfering, but she is also fiercely loyal. Family loyalty, no matter what, is essentially the guiding principle of her life.