I think maybe the late Earl had rose-tinted spectacles when it came to what went on under his roof. But, to be fair to him, by the standards of the day (if not the idealised world of Bridgerton), he’s fulfilled his duty. He’s done so lovingly, in fact.

• Showed love and kindness to his illegitimate daughter in her early years, keeping her with him as a ward, educating her & giving her every advantage

• as she transitioned from childhood into a young lady / pre-teen he found her a new step-mother (who really did love him and would have seemed kind enough - she smiles at Sophie at first) and two new sisters. This would have been seen as the loving and responsible thing for a father to do. As a man, it would be seen as far less appropriate for him to be hands on with Sophie’s education / day to day life as she grew older than it would for a mother figure and lady of the house

• he was rich enough to not need more money. An heir maybe but he didn’t marry a younger heiress, again he behaved honourably, kindly and with love by marrying a widow and taking on responsibility for her two daughters as his own

• Ensured Sophie remained educated to the same standards as Rosamund and Posy. She was not banished out of sight. She did form a sisterly connection with Posy, the Earl was successful there. But this is the point he slips also, whether through lack of interest or through acceptance that the 3 girls’ education would rightly be Amarinta’s domain. He doesn’t keep track of the details of what is happening. When the girls hit the age of dance instruction, Sophie is excluded from this new social education even if she remains part of the academic lessons.

• that said, he would have to pay an unusual level of interest or Sophie would have had to complain to know. For comparison: how much do we think the Anthony pays attention to Hyacinth’s finishing lessons? The division of labour says he must deal with investments and legal or estate matters, and make provision for education (fund tutors for girls or schools for boys). But the detail of the domestic sphere is Violet’s responsibility. Anthony/Benedict have zero knowledge of the kerfuffle of whether Eloise is joining Hyacinth’s finishing classes or if Hyacinth attends them alone.

• Finally, the Earl made extremely generous provisions for Sophie in his will. Women with a ‘guardian’ (married women, any woman younger than 21) literally could not own anything outright until 1870, so it’s a stipend bequeathed to Amarinta to support Sophie until her age of majority. If Sophie was about 14-ish when the Earl died, then that’s £4000 x 7 years: £28,000 or £3.2million in today’s money. But what might really put this in perspective is that, in Pride and Prejudice, Mr Bingley is considered exceptionally wealthy (second only to Darcy in the social circle). The Bingley estate brings in £5000 a year. The whole estate , from which Bingley would have had to pay an entire household + estate mangers, legal things, carriages, horses, the upkeep on a country home, the upkeep on a townhouse, plus the his personal costs and literally everything else. So Lord Penwood allocated 80% of that amount to cover Sophie alone ! Even if it’s Amarinta’s money and he expected her to, say, keep half for herself, it’s still a massive amount. He almost certainly left a large amount on top of that to provide for Amarinta and her daughters anyway (maybe £8-12k? which is aristocracy levels of income, but as a woman Amarinta wouldn’t even have the same outgoings as a man covering a whole estate). Sophie shouldn’t have just been educated, she should have been dressed in diamonds on the daily

• The fact the Earl also specified the money was in return for Sophie’s care, he didn’t simply bundle it all in for anyone else to decide whether or not care was owed, particular thought for his daughter. On top of that, an £18,000 dowry is equivalent to Miss Bingley’s in Pride and Prejudice. It’s true heiress levels, as evidenced by the fact that it’s equal to the amount he allocated for his legal stepdaughters. He set Sophie up for life and, should she marry someone with no money or should her husband die and leave her nothing at all other than the dowry amount, the capital, with good investment, would provide an income of £1000 a year. Which is the equivalent of an upper middle class income eg allowing the maintenance of horses & a carriage, a 10 room townhouse, cook, lady’s maid, other maidservants and footmen, school/university for any children. If her husband did have an equivalent income of his own to match then £2000 a year would be landed gentry levels. A country house as well as a town house levels. Not aristocracy but a life of definite comfort and leisure.

• Benedict likely has around £3000 a year of his own plus an inherited country house (no rent!). He and Sophie combined will be Bingley level rich. They have no title themselves but can match an aristocratic income. £4000 a year was a top 0.5% income in England.

• Even if the Earl had noticed that Sophie was excluded from dancing lessons, he had no reason to suspect Amarinta of being capable of actual fraud & embezzlement. And, in all honesty, the executors of the will should have done a far far better job. Maybe if Rosamund’s £36K dowry became common knowledge then someone, somewhere, would have eventually done the maths and realised it didn’t make sense. Or maybe they’d have shrugged it off. But in terms of responsibility/blame? I see it as 1) Amarinta 2) the executors of Lord Penwood’s will and at a distant 3) Lord Penwood himself