<prompt> Human: I started investing in a Vanguard 2045 mutual fund account about 10 years ago shortly after I graduated college. Im comfortable with the fact that its essentially set it and forget it, and its been great. Since then, my current company 401k, Roth IRA as well as my spouses, and rollover IRAs all use the same Vanguard 2045 fund investment.I understand that the fund itself is diversified, but is there anything wrong if this single fund is essentially the only thing I invest in across the board?  <response>: Theres absolutely nothing wrong with having this one diversified fund across all of your accounts. 