Need more info:
is this cash money sitting in a saving account right now, or was it a QRDO that is sitting in a 401k/IRA (this is a court ordered split of any retirement accounts from the marriage type of thing).
If she has the holdings - cash or stocks/mutual funds/bonds - ALREADY inside a tax deferred account (fingers crossed) then it's super easy: figure out an asset allocation, then invest accordingly). 401k/403b/rollover or traditional or Roth IRAs are all tax deferred (Roth is an after tax contibution account, but for her purposes, it's okay to sell/buy). Any of those types, then it doesn't matter what the holdings currently are, she can sell them with no taxable events generated and buy whatever fits her AA.
If it is cash or taxable investment account, then it gets a bit more fussy. You are limited by how much $ you can put into a tax deferred account if she has one or at least has the ability to open one. And the "fussy" part is in the details - taxable moves here - cash and investment accounts for instance - require looking at how the buy/sells might screw around with her overall taxable income generated and could cause some extra $ owed (or if there are losses, tax loss write offs!) due to dividends and capital gains generated and considered taxable. So always a good idea to proceed carefully, so you can minimize the tax hits here. It sounds scarier than it is, but it's really important to not go crazy with the buy sell thing in a taxable account. Buy and HOLD is a great thing, and making sure any holding in a taxable account are as tax efficient as can be is also smart.
https://www.bogleheads.org/wiki/Principles_of_tax-efficient_fund_placementIf she is working, does she have access to retirement accounts? 401k/403b? Does her company match any %? If so, who with? Vanguard/Fidelity/T Rowe all good. American Funds or below? Not so much...
Review the investment order for help then:
https://forum.mrmoneymustache.com/investor-alley/investment-order/So figuring out her asset allocation... that's a bit more complicated, but really just requires either some reading and pondering on her part, and it's fine to let things sit for a bit while she gets it figured out.
https://www.bogleheads.org/wiki/Investment_policy_statement^this is the road map/blueprint for what she wants out of her life, for her future, what she'll do if X, Y Z happens... can be as simple or complicated as she wants.
https://www.bogleheads.org/wiki/Asset_allocation^once she gets her IPS, then it's on to an AA. Definitely easy to set up a basic AA using a 2 or 3 fund portfolio and simple is always best.
https://www.bogleheads.org/wiki/Managing_a_windfall^nice overview