The Small-Cap Growth Index Admiral fund is a mutual fund within the Vanguard Mutual Funds family. This fund has 30 other funds which are extremely similar to it.
Within the Vanguard Mutual Funds family of funds, the most positively correlated other funds are Explorer Admiral Shares, Explorer, Extended Market Index Admiral Shares, Small-Cap Index Admiral Shares, Explorer Value.
Outside of the Vanguard Mutual Funds family, the most positively correlated other funds are Vanguard - Small-Cap Growth, Fidelity - Spartan Small-Cap Index Fund - Investor Class , iShares - Russell 2000 ETF, Fidelity - Spartan Small-Cap Index Fund - Fidelity Advantage Class , Schwab - Small-Cap Core.
There are multiple other funds which have extremely high correlation to Vanguard Mutual Funds's Small-Cap Growth Index Admiral fund.