She noticed Joseph was dismissive of Simon's words.
Initially, after their wedding, inside Hampton, there was no nanny, and only hired short-period workers were there as Joseph did not want to see other people around Hampton disturb their lives, which Irish agreed to.
Irish had been thinking about what kind of sweet words Joseph could use to describe their married life or vowed to what to do in the future. But when he returned to New York, he didn't say anything about the marriage promise but told her about his shares, options, dividends, and his investments in Swiss banks. Before that, she only knew all the passwords for his bank cards. After Joseph shared all his assets, suddenly, Irish realized how huge his net worth was.
She thought, 'Was this his promise?'
The fact that such a man presented himself to her without reservation meant that he trusted her enough and was willing to give her all the happiness.